This invention relates to a new and improved inked ribbon winding device for a printing apparatus including a new and improved inked ribbon cartridge for a printing apparatus.
The prior art includes various kinds of devices for dispensing and winding inked ribbon during printing operations. Some such devices employ ribbon cartridges to dispense inked ribbon to a printing position, and to rewind the ribbon on a takeup spool after printing. The ribbon is drawn across the printing position by directly or indirectly driving the takeup spool.
In direct drive devices, a takeup spool spindle is directly driven. In indirectly driven devices, a rotatable member engages and drives the surface of the ribbon being wound about the takeup spool. In the latter type of device, the rotatable member is usually movable to account for ribbon accumulation on the takeup spool. In both cases, a complicated mechanism is generally required to drive the takeup spool.
Additionally, in the operation of a printing apparatus it is generally desirable to feed the ribbon to the printing position at a relatively constant rate. Accordingly, the outer circumference of the ribbon being wound at the takeup spool has to move at a relatively constant speed. However, the circumference of the roll of ribbon being wound about the takeup spool continually increases during printing operation. As a result, if the rotatable member axially drives the takeup spool mounted thereon at a constant rate, the speed of the ribbon moving across the printing position continually increases. A mechanism in the winding device for diminishing the angular velocity of the rotatable member is accordingly required in such a winding device.
When the takeup spool is rotated through engagement between the rotatable member and the ribbon wound about the takeup spool, the rate of movement of the ribbon is generally uniform. However, to insure this uniform rate of movement, means must be provided to maintain an effective non-slipping, mechanical engagement force between the rotatable member and the ribbon on the takeup spool. Each of the abovediscussed drives can require a complicated arrangement of parts including gears, links, levers, cams and ratchet wheels.
Accordingly, a primary object of the present invention is to provide a new and improved printing apparatus including a new and improved inked ribbon winding device.
Another object of the present invention is to provide a new and improved inked ribbon cartridge for use in a printing apparatus.
Another object of the present invention is to provide a new and improved inked ribbon winding device having an inked ribbon cartridge for use in a printing apparatus and driven by a rotatable member rotating on a fixed axis in a support structure and driving a ribbon takeup spool through engagement with ribbon wound thereon.
Another object of the present invention is to provide a new and improved inked ribbon winding device having an inked ribbon cartridge which is slidably mounted on a baseplate to effect engagement between a rotatable drive member and ribbon wound on a takeup spool in the cartridge and to provide automatic movement of the cartridge to compensate for increases in the radius of the ribbon roll being wound on the takeup spool.
Another object of the present invention is to provide a new and improved inked ribbon cartridge wherein its dispensing and takeup spools are closely situated in an arrangement effective to reduce cartridge size and materials.
Another object of the present invention is to provide a new and improved inked ribbon winding device which feeds ribbon to a printing position along a preferred path.
Still another object of the present invention is to provide a new and improved inked ribbon winding device which biases a cartridge containing inked ribbon into engagement with a rotatable member whereby the winding mechanism can be simple and reliable.